20-11-2012, 01:52 PM
EDGE DETECTION AND EDGE ENHANCEMENT OF IR IMAGES
EDGE DETECTION AND EDGE.pptx (Size: 464 KB / Downloads: 41)
OBJECTIVE
The principal objective of enhancement is to process an image so that the result is more suitable than the original image for a specific application.
INTRODUCTION
To enhance the blur image in order to get the clear image with its original characteristics.
For example, a method that is quite useful for enhancing X-ray images may not necessarily be the best approach for enhancing pictures of Mars transmitted by a space probe.
EDGE ENHANCEMENT:-
Edge enhancement is an image processing filter that enhances the edge contrast of an image or video in an attempt to improve its acutance.
The filter works by identifying sharp edge boundaries in the image and increasing the image contrast in the area immediately around the edge.
Edge enhancement can be either an analog or a digital process.
edge enhancement is used for improving the perceived sharpness or acutance of an image.
A modern television set's "sharpness" control is an example of edge enhancement.
Edge enhancement can be applied in the horizontal or vertical direction only, or to both directions in different amounts.
EDGE DETECTION
Edge information in an image is found by looking at the relationship a pixel has with its neighborhoods.
If a pixel’s has neighbors with widely varying gray levels, it may present an edge point.
If a pixel’s gray-level value is similar to those around it, there is probably not an edge at that point.
Edge detection is a fundamental tool particularly in the areas of feature detection and feature extraction
IMAGE ENHANCEMENT IN THE SPATIAL DOMAIN
Spatial domain refers to the image plane itself, and approaches in this category are based on direct manipulation of pixels in an image.
When an image is processed for visual interpretation, the viewer is the ultimate judge of how well a particular method works.
Visual evaluation of image quality is a highly subjective process .
When the problem is one of processing images for machine perception, the evaluation task is somewhat easier.
Image Operations on a Pixel Basis
Images were represented in the form of matrices.
We refer to an operation like “dividing one image by another,” we mean specifically that the division is carried out between corresponding pixels in the two images.
If f and g are images, the first element of the image formed by “dividing” f by g is simply the first pixel in f divided by the first pixel in g; of course, the assumption is that none of the pixels in g have value 0.